System for supplying heated air for use on aircraft



y 8, 1951 E. P. PALMATIER 2,551,597

SYSTEM FOR supmrms HEATED AIR'FOR usE on AIRCRAFT ori i ial Filed Sept. 20, 1943 3nventor Patented May 8, 1951 UNITED STATES NT OFFICE SYSTEM FOR SUPPLYING HEATED AIR FOR USE ON AIRCRAFT Everett P. Palmatier, Solvay, N. Y., assignor to Curtiss-Wright Corporation, a, corporation of Delaware 2 Claims.

My invention relates to systems for supplying heated air for use on aircraft.

My invention has reference to a system comprising a pipe through which a stream of air flows under pressure through a heat-exchange zone, said system further comprising a valvecontrolled pipe which forms a by-pass around said zone.

My invention has further reference to a system comprising means for controlling a condition, for example, pressure of the stream of air, said system further comprising means responsive to different conditions of said stream of air for jointly actuating said control means.

My invention has further reference to a system comprising an air scoop for causing a stream of air to flow under pressure through a heatexchange zone, said system further comprising means for varying a condition of said stream of air while passing toward the heat-exchange zone.

Various other objects, advantages and features of my invention will become apparent from the following detailed description.

My invention resides in the heat-exchange system, novel control features, arrangements and combinations of the character hereinafter described and claimed.

This application is a division of application Serial No. 503,143, filed September 20, 1943, now Patent No. 2,507,044 of May 9, 1950.

For an understanding of my invention and for an illustration of one of the forms thereof, ref erence is to be had to the accompanying drawings, inwhich:

Figure 1 is a schematic view showing the sup :1:-

ply system of my invention; and

Fig. 2 isa sectional view illustrating a control mechanism included in-my novel system.

Referring to Fig. 1, I have shown an aircraft surface W'which, for example, ma be the forward surface of a wing. Projecting in the normal direction of aircraft flight is an air scoop 5 adapted to supply air to a pipe 2 having branching therefrom an upwardly extending pipe 3 which terminates: above the surface W at the rear of theair scoop ii. Disposed in the pipes 2 and 3 are the respective valves 4 and 5. which are operated by control mechanism C of the character shown in Fig. 2.

The-contro1 mechanism C may be of any suit- 1 8316101131301181 and, as illustrated, it comprises a 1 pair. of housings E, l secured to each other in flanged relationandseparated from each other by a plate 8. Secured to the plate 8 are the inner and outer bellows-9 and it forming sealed chambers, respectively, and having a depending rod H secured to the upper plate of each, said rod ii being slidably mounted in and with respect to the aforesaid plate 8 and also with respect to a nut l2 which is threaded through a member I3 secured to and closing the lower surface of the housing 7. Within said housing i, the rod 5 i has secured thereto a disk M which faces a similar disk l5 mounted on the nut IS. The rod H is slidable with respect to the disk 55 and, confined between the two disks M and i5, is a helical spring 15 which biases the rod i l in an upward direction.

As shown in Fig. l, the rod ll of the control mechanism C has connected thereto a member ii to which each of the valves 4 and 5 is connected. Communicating with the chamber defined by the exterior surface of the bellows l0 and the interior surface of the housing 6 is a pipe [3 which communicates with the aforesaid pipe 2 beyond the junction thereof with the pipe 3. Accordingly, operation of the valves 4 and 5 is responsive to the pressure of the air passing through the pipe 2 downstream of its juncture with the pipe 3, and this air is controlled to constant pressure.

The pipe 2 extends through a suitable heating zone exemplified, in the example shown, but not necessarily, by a housing 28 having inlet and outlet ports traversed by the hot exhaust gases from the aircraft engine, convolutions of the pipe 2 being. suitably arranged in said housing 28.

A pipe 29 communicates with the pipe 2 adjacent the entrance side of the heat-exchange zone. This pipe 2Q by-passes said heat-exchange zone and is disposed in communicating relation with the pipe 2 adjacent the exit side of the heatexchange zone. Disposed at the juncture of the pipes 2 and 29, at the entrance side of the heatexchange zone, is a valve 36 adapted to be actuated by a link (it pivoted to the lever 32 of a control mechanism Cl which is a duplicate of the control mechanism illustrated in Fig. 2. As regards the control mechanism Cl, a pipe 35 replaces the pipe 53 of the control mechanism C, said pipe 33' terminating in a thermal bulb 3 disposed in the pipe 2 beyond the junction thereof with the discharge end of the pipe 29, the bulb 34, the pipe 33 and the space in the associated housing t exteriorly of the outer bellows it being filled with a suitable control medium, either vapor, liquid or a gas. Thus the control mechanism CI in conjunction with the valve 30 maintains the mixed air from the pipes 2 and 29,

downstream of the heat exchanger 28, at constant temperature.

The pipe 2, adjacent the discharge end thereof, has disposed therein a valve 35 which is controlled by the quantity of air traversing the pipe 2. Accordingly, the valve 35 has connected thereto a link 35 which is pivoted to a suitably supported lever 3'5 controlled by a pair of control mechanisms C2 and C3 of the character illustrated in Fig. 2. As regards the control mechanism C2, a pipe 38 replaces the pipe I8 01 the control mechanism C, said pipe 38 terminating in an angular section 380. disposed in a section of the pipe 2 beyond the junction thereof with the discharge end of the pipe 29 mechanism C2 operates to move the valve 35 to maintain constant flow of air.

As regards the control mechanism C3, a pipe 39 replaces the pipe is of the control mechanism C, said pipe 39 opening to the ambient air. The pipe 39 and the space in the associated housing 6 exteriorly of the outer bellows l are in communication, the interior of the bellows being evacuated or containing a fixed quantity of elastic fluid to provide an altitude or air density compensation. Hence, the rod ll of the control mechanism C3 varies in position in accordance with the atmospheric pressure.

The rods I! of the pair of control mechanisms C2 and C3 are pivoted, respectively, to the opposite ends of a lever 4! which by a link 42, is pivoted to the lever 31. Accordingly, the lever 3'], link 36 and the valve 35 take a position which is dependent jointly upon the pressure of the ambient air and the quantity of air passing through a section of the pipe 2 beyond the juncture thereof with the aforesaid pipe 29.

As regards the form of my invention herein disclosed, the control mechanism C for the valves 4 and 5 holds these valves in such respective positions that the intake pressure of the air passing through the pipe 2 beyond the junction thereof with the pipe 3 has a desired value. In case this intake pressure becomes too high, the control mechanism C operates to move the valve 4 to a more closed position and the valve 5 to a more open position. Should such intake pressure become too low, an operation the reverse of that described is effected on the valves 4 and 5.

The control mechanism CI for the valve 35 is operated in accordance with the temperature of the air passing through that section of the pipe 2 beyond the heat-exchange zone. In case the temperature of the air passing through said last named pipe section becomes too high, the control mechanism Cl moves the valve to such position that more of the air by-passes the heat-exchange zone by way of the pipe 29. Should the temperature of the air in said last named pipe section become too low, an operation is performed the reverse of that described whereby the pipe 29 is throttled to cause more air to pass through the heat-exchange zone.

As hereinbefore stated, the position of the valve is determined jointly by the quantity of air passing through that section of the pipe iii and the interior surface 2 beyond the junction thereof with the pipe 29 and also by the ambient air pressure.

The heated air emergin from the outlet end of the pipe 2 may be utilized for any suitable purpose on the aircraft as desired. For example, this stream of heated air may be utilized to heat any selected aircraft surface to prevent the formation of ice thereon or to melt ice which has already been formed thereon.

As illustrative of some uses of the stream of heated air, reference is to be had to Fig. 1 which, in a diagrammatic manner, shows a propeller hub having angularly related sockets for the reception of the respective propeller blades 5|. Associated with the hub 50 is a spinner 42 and, exteriorly thereof, cuffs 53 are disposed around the respective blades 5|. The parts thus described are rotatable together as a unit. Suitably secured to these rotatable parts is an annular housing 54 maintained in sealed relation as at 55 with a second annular housing 56 suitably secured in fixed position with respect to the rotatable housing 54.

As shown, the outlet end 2b of the pipe 2 communicates with and discharges a main stream of heated air into the sealed chamber defined by the housings 54 and 56. Secured to the housin 54 for rotatable movement therewith and communicating with said chamber are four pipes 51, 58 and 59, 59 traversed, respectively, by secondary of streams of heated air. The pipe 5'! passes heated air into the spinner 42 and, particularly, into engagement with the interior surface of said spinner 42 from which such heated air may pass into heattransferring relation with the blade cuffs 53 by way of the respective passages 51a and, further, heated air from the spinner 52 may pass into the hollow blades 5i by way of passages 57b. The pipe 2 58 terminates interiorly of the hub 50 and conveys heated air into the space defined thereby, such heated air thereafter passing outwardly into and through the interior chambers defined by the respective propeller blades 5| each of which comprises an air-discharge passage at or near the end thereof. The pipes 59 are bent angularly and communicate with the respective chambers formed at the leading edges of the cuffs 53, to which they convey heated air from the chamber 55, 56.

From the foregoing description, it will be understood that the flow of air through the pipe 2 is established and maintained in response to movement of the aircraft through the air. Obviously, a pump, or equivalent, may be utilized for effecting such passage of air through the pipe 2 and, if desired, it will be understood that the pump may be utilized booster-fashion to increase the flow of air through said pipe 2.

While the invention has been described with respect to a certain particular preferred example which gives satisfactory results, it will be understood by those skilled in the art after understanding the invention, that various changes and modifications may be made without departing from the spirit and scope of the invention and it is intended therefore in the appended claims to cover all such changes and modifications.

What is claimed as new and desired to be se cured by Letters Patent, is:

1. A system for obtaining a supply of heated air on an aircraft, said system comprising a pipe, an air scoop connected with said pipe for causing a stream of air to flow therethrough under pressure, a second pipe branching from said first pipe and terminating in a section facing from said air scoop, a valve in each of said pipes, and. control mechanism responsive to pressure downstream of the valves for actuating said in unison to maintain substantially constant pressure in said pipe.

2. A system for obtaining a supply or" heated air on an aircraft, said system comprising a pipe, an air scoop connected with said pipe for causing a stream of air to flow therethroizgh under pressure, a second. pipe branching from said first pipe and terminating in a section facing from said. air scoop, a valve in each of said pipes, and pressure-responsive control mechanism for jointly actuating said valves responsive in its op- 1 erative to the air pressure downstream of sai-ci valves.

EVERETT P. PALMATIER.

8 REFERENCES orrsn The following references are of record in the file of this patent:

UNITED STATES PATENTS 

